APi 620 Storage Tanks

•  Spheroid: A spheroid tank is a fully welded, spherical or nearly spherical pressure vessel designed to store liquids and gases under moderate pressure. Its geometry allows uniform stress distribution, making it ideal for liquefied petroleum gases (LPG), propane, or butane storage.

• Noded Spheroid: A noded spheroid consists of multiple spherical segments connected at “nodes” to form a larger volume storage system. This configuration combines the structural efficiency of spheres with easier fabrication and modular assembly, suitable for large-capacity hydrocarbon or chemical storage.

 Egg-Shaped Digester: An egg-shaped digester is a tall, curved-bottom pressure vessel commonly used in wastewater treatment plants. Its shape promotes continuous mixing and prevents sediment buildup, enhancing digestion efficiency and gas collection in anaerobic sludge digestion applications.

• Low Temperature Tank (Annex R): Designed per Annex R of API 620, these low-temperature tanks at temperature as low as -60 °F conditions. Commonly used to design tanks to store products like liquified ammonia and propane They feature insulation and specialized materials to maintain containment integrity and prevent brittle fracture.

• Cryogenic Tank (Annex Q): Cryogenic tanks built under Annex Q are engineered for extremely low temperatures (down to -320°F / -196°C), storing prodcuts like LNG, ethylene, liquid oxygen (LOX), or liquid nitrogen (LIN). They typically include inner and outer shells with high-performance insulation for thermal protection.

• Elevated Cone-Bottom Tank: An elevated cone-bottom tank has a conical bottom supported on legs or a structural frame, allowing easy drainage and product discharge. These are often used for liquids requiring full drainage, such as water, chemicals, or process slurries, and may be pressurized or atmospheric depending on service.